Chord playing attachment for stringed musical instruments



y 27, 1969 E. F MITCHELL, JR 3,446,108

CHORD PLAYING ATTACHMENT FOR STRINGED MUSICAL INSTRUMENTS IN VENTOR. 7' 6' H1544 J6 BY Filed Oct. 10, 1967 May 27, 1969 E. F. MITCHELL, JR 3,446,108

CHORD PLAYING ATTACHMENT FOR STRINGED MUSICAL INSTRUMENTS Filed Oct. 10, 1967 Sheet 2 012 IN ENTOR. 6464 A M/TCHEA 4, J6

United States Patent Int. (:1. Gd 3/08 US. Cl. 84-317 7 Claims ABSTRACT OF THE DISCLOSURE A chord playing attachment intended particularly for guitars wherein a plurality of string engaging fingers are adjustably mounted on a series of arms traversing the strings of the guitar; the arms, in turn being depressed individually or in multiple by a series of pivotally mounted yokes operated by finger levers and an interposed spring so that manual depression of a single lever will cause selected fingers to engage the guitar strings thereby to produce a predetermined chord.

This application is a continuation-in-part of my copending application Ser. No. 419,616 filed Dec. 18, 1964, and my copending application Ser. No. 483,141 filed Aug. 27, 1965.

Background of the invention The following patents are known to applicant:

545,963, Ling; 589,658, Kelman; 757,251, Berglund; 957,681, John; 2,450,210, Sprague; 2,669,151, Maccaferri; 2,790,344, Brimhall; 3,129,626 Granius; Australian Patent 1,469.

The present invention relates to an improved chord playing attachment for stringed musical instruments, such as but not limited to guitars, which enables even an unskilled musician, by selecting and manually depressing a particular key, to produce a corresponding chord.

It is an object of the present invention to provide a device which may be readily attached to the neck of, for example, a guitar at various selected positions, depending upon the desired pitch.

Another object is to provide a chord playing attachment wherein a plurality of parallel arms traverse the strings of the musical instrument, each arm adjustably receiving a string engaging finger so that the finger may be moved along the arm to engage any selected string.

Another object is to provide a chord playing attachment wherein selected finger operating arms are individually engaged by force transmitting means in the form of compression springs; a chord producing set of springs being mounted in one of a set of chord playing yokes, and the yokes being arranged to receive the springs in any position corresponding to any of the finger op erating arms, whereby any combination of chords may be selected within the range of the attachment.

A further object is to provide a chord playing attachment wherein the members of the set of chord playing yokes are pivotally mounted on a common shaft and readily removable therewith as a unit, whereby different sets of chord playing yokes in which different chords have been selected may be quickly interchanged.

Another object is to provide a chord playing attachment wherein each yoke member is adapted to receive at selected locations a series of springs for transmitting movement to the set of string engaging fingers, said springs determining the force applied to said fingers.

3,446,108 Patented May 27, 1969 "ice Description of drawings FIGURE 1 is a plan view of a guitar showing the chord playing attachment mounted thereon.

FIGURE 2 is an enlarged perspective view of the chord playing attachment, with a guitar shown fragmentarily.

FIGURE 3 is an enlarged sectional view, taken through 3-3 of FIGURE 1.

FIGURE 4 is a partial sectional, partial side view, taken from 44 of FIGURE 3.

FIGURE 5 is a fragmentary perspective view, showing one of the depressing springs and an adjacent portion of finger supporting member.

FIGURE 6 is a fragmentary sectional view, taken through 66 of FIGURE 3, illustrating the manner in which the chord playing yokes are removably held in position.

The chord playing attachment may be adapted to various stringed instruments. For purposes of illustration, however, the attachment is shown in conjunction with a guitar 1, having a neck 2, over which extends strings 3. A series of frets 4 underlie the strings.

The chord playing attachment includes an outer frame 5, having parallel side walls 6 located at one side of the guitar neck and connected by a back wall 7. A pair of projections 8 extend from the side walls under the neck 2. These projections 8 are provided with a pair of fixed clamp fingers 9, having tips overlying one margin of the neck, and a pair of movable clamp fingers 10, having tips overlying the opposite margin of the neck. The movable clamp fingers 10 are mounted on slide bars 11 in such a manner that the fingers 10 may be moved toward the neck for engagement therewith as indicated in FIGURE 3. Each projection 8 is provided with a set screw 12 located under the neck 2 and equipped with a clamp disk 13 which engages the underside of the neck so that the outer frame is securely held in place.

An essentially U-shaped inner frame 14 is provided which includes side members 15, secured within the upper margins of the side walls 6, and extending over the neck 2 of the guitar in spaced relation therewith. The side members 15 terminate at the far side of the neck 2 from the side walls 6 and are joined by a front member 16, having a series of vertically extending guide slots 17, closed at their upper ends by a removable retainer strap 18.

Within the outer frame 5, the side members 15 are enlarged downward so as to support therebetween a pair of journal shafts 19, defining a vertical plane. The journal shafts receive vertically aligned pairs of parallel links 20. Each pair of parallel links is joined by pivots 21 to a finger supporting member 22. Each finger supporting member includes a vertically depending post 23 to which the pivots 21 are attached. The upper end of each post is joined to a forwardly extending arm 24 and a rearwardly extending part 25. Each finger supporting member is therefore essentially T-shaped in side aspect, the arm 24 forming one arm of the T, being elongated and extending over the neck 2 and into a corresponding guide slot 17.

Each arm 24 is bifurcated by a longitudinal slot 26. A set of playing fingers 27 is provided, each playing finger including a vertically disposed U-shaped end 28, which is adapted to be inserted in the longitudinal slot 26 of a corresponding member 22. The sides of the U-shaped end frictionally grip the supporting member so that the playing finger may be moved transversely with respect to the guitar strings 3, and thus be positioned over any selected string. Each playing finger also includes a laterally and downwardly directed end 29, the extremity of which is provided with a pad 30, adapted to engage and depress a selected string, as indicated in FIGURE 4.

The set of finger supporting members 22, and the playing fingers 27, are held in a raised position by a leaf spring comb 31, comprising a set of forwardly directed leaf springs connected to a common base clamped between a pair of mounting plates 32, secured between the underside of the side members 15, as shown in FIGURE 3.

Each finger supporting member 22 is provided at its upper edge, in the region above the depending post 23, with a series of upwardly directed spring retainer bosses 33. The back wall 7 of the outer frame extends above the finger supporting members 22, and includes a forwardly directed portion 34. The side walls 6 underlying the forwardly directed portion are provided with horizontal journal slots 35, open at their forward ends. The slots 35 receive a journal shaft 36, which is retained in place by a pair of retainer latches 37, shown best in FIGURE 6.

A set of yokes 38 are provided, each yoke being U- shaped in plan and comprising parallel arms 39, joined by a cross bar 40. The cross bars differ in length so that the parallel arms nest within each other so that the yokes are individually pivoted on the journal shaft 36.

Each cross bar 40 is provided with a plurality of depending spring retainer bosses 41, corresponding in number to the finger supporting members 22. A set of coil springs 42 is provided. The lower ends of the springs 42 are adapted to fit over spring retainer bosses 33, corresponding to the selected depending boss 41. The springs, acting in compression, transmit downward movement of a yoke 38 to a corresponding finger supporting member 22.

Means are provided for individually depressing the yokes 38, and as shown in the drawings, this means includes a finger lever 45 for each yoke 38, respectively. The levers 45 could be pivoted on the frame and each individually contact its respective yoke cross bar, or as shown, each of the cross bars 40 of the yokes 38 may be provided with a pair of upstanding posts 44. The pairs of posts are offset from each other and receive therebetween a series of finger levers 45. Each finger lever includes an essentially horizontal portion 46 pivotally connected to a corresponding pair of posts 44 by a cross pin 47. The finger levers also include a depending portion 48 which bears against the front edge of the forwardly directed portion 34 of the back wall 7.

The horizontal portions of the lever 45 extend over the neck 2 of the guitar for manual engagement by the fingers of the musician. A front cover 49 encloses the forward portion of the inner frame 14.

Operation of the chord playing attachment for stringed musical instruments is as follows:

The attachment is readily clamped to the neck of the guitar or other stringed instrument at any desired point; the choice of location is determined by the key in which it is desired to play the chords. Before mounting the attachment, the desired number of playing fingers 27 are mounted on the supporting members 22 and located so as to engage selected strings. Each supporting member may be provided with a playing finger, or for that matter, more than one playing finger, or the playing fingers may be mounted on selected supporting members, all according to the number and type of chords it is desired to play.

A single chord playing unit comprising the yokes 38 and finger levers 45, or several such units may be provided. If more than one unit is used, the units are readily interchangeable by raising the retainer latches 37 and inserting or removing the journal shaft 36 laterally from the slots 35. Each yoke receives a group of springs 42 corresponding to a chord and positioned along the cross bar 40 to engage the desired finger supporting members 22 so that depression of any of the finger levers 45 will depress the proper strings so that when the guitar strings are sounded, a preselected chord is played.

By reason of the fact that the playing fingers 27 may be adjusted to engage any of the strings and may be mounted on any or all of the finger supporting members 22, a maximum range of choice is provided. Still further,

by reason of the fact that the springs 42 may engage any of the finger supporting members 22, the range of choice is further increased.

It should be noted that the springs 42 are relatively stiff in comparison to the leaf-springs comprising the comb 31 and are not compressed unless the finger lever is depressed. The leaf springs readily hold the finger supporting members 22 and their playing fingers 27 in a raised position, with the forward extremities of the members 22 engaging the retainer strap 18. When a selected finger lever 45 is depressed, and a corresponding yoke 38 is pivoted, the springs 42 compress slightly, overcoming the counter force of the springs 31 until the strings 3 are engaged. Further depression of the finger levers 45 increases the pressure on the strings 3 due to further compression of the springs 42. However, the actual force exerted is determined by the springs 42, not by the musician, if the finger levers 45 are fully depressed.

While a particular embodiment of this invention has been shown and described, it is not intended to limit the same to the details of the construction set forth, but instead, the invention embraces such changes, modifications and equivalents of the various parts and their relationships as come within the purview of the appended claims.

I claim:

1. A device for use with a musical instrument having a neck and having strings tensioned over frets provided on a surface of the neck, the device comprising, in combination: a frame, means for mounting the frame on the neck of the instrument, a plurality of parallel arms each extending transversely over the strings, a finger mounted upon each of said arms and engageable with one of the strings, respectively, parallel pivot links on the frame supporting each arm for parallel movement between a raised position in which its finger is raised clear of the strings and a depressedposition in which its finger depresses the string against a fret, resilient means for lifting each arm to raised position, a group of U shaped nested yokes pivotally mounted on said frame about a common axis parallel to said strings, each yoke having a bar extending over said arms in a direction parallel to said common axis, each bar having a plurality of spaced elements for directly engaging and depressing a plurality of said arms.

2. The combination set forth in claim 1 wherein each of said spaced elements comprises a coil compression spring.

3. The combination set forth in claim 1 wherein each finger is adjustably mounted for movement along the length of its respective arm.

4. The combination set forth in claim 1 wherein a plurality of manually operable levers are provided, each lever being operatively associated with said frame and one of said arms, respectively, for moving the arm to its depressed position against the action of said resilient means.

5. The combination set forth in claim 4 wherein each lever is pivotally connected to one of said yokes, respectively, and has a portion contacting said frame.

6. The combination set forth in claim 1 wherein removable means on the frame pivotally support all of said yokes, said yokes and pivot means being removable and replaceable as a unit with respect to said frame.

7. The combination set forth in claim 6 wherein a journal shaft pivotally supporting said yokes is movable laterally into slots provided in the frame.

References Cited UNITED STATES PATENTS 589,658 9/1897 Kelman 84317 2,790,344 4/ 1957 Brimhall 84-317 3,129,626 4/ 1964 Granius 843 17 RICHARD B. WILKINSON, Primary Examiner.

LAWRENCE R. FRANKLIN, Assistant Examiner. 

